The invention relates to molecules, compositions and methods that can be used for the treatment and prevention of HSV infection. More particularly, the invention identifies epitopes of HSV proteins that can be used for methods, molecules and compositions having the antigenic specificity of HSV-specific T cells, and in particular, of CD8+ as well as CD4+ T cells.
Cellular immune responses are required to limit the severity of recurrent HSV infection in humans. Initial genital HSV-2 infections are prolonged and severe, while recurrences are less severe and more frequently asymptomatic. Resolution of primary HSV-2 infection is associated with infiltration of antigen-specific T cells, including CD8+ cytotoxic T lymphocytes (CTLs). Serial lesion biopsy studies of recurrent HSV-2 infection in humans has shown a shift to CD8+ predominance as lesions mature and correlation of local CTL activity with virus clearance (Koelle, D M et al., J. Clin. Invest. 1998, 101:1500-1508; Cunningham, Ala. et al., J. Clin. Invest. 1985, 75:226-233). Thus, HSV antigens recognized by CD8+ CTL can be used for novel therapies and vaccines.
The complete DNA sequence of herpes simplex virus (HSV) is approximately 150 kb and encodes about 85 known genes, each of which encodes a protein in the range of 50-1000 amino acids in length. Unknown are the immunogenic epitopes within these proteins, each epitope approximately 9-12 amino acids in length, that are capable of eliciting an effective T cell immune response to viral infection.
There remains a need to identify specific epitopes capable of eliciting an effective immune response to HSV infection. Such information can lead to the identification of more effective immunogenic antigens useful for the prevention and treatment of HSV infection.
The invention provides HSV antigens, polypeptides comprising HSV antigens, polynucleotides encoding the polypeptides, vectors, and recombinant viruses containing the polynucleotides, antigen-presenting cells (APCs) presenting the polypeptides, immune cells directed against HSV, and pharmaceutical compositions. The pharmaceutical compositions can be used both prophylactically and therapeutically. The antigens of the invention are recognized by T cells recovered from herpetic lesions. The invention additionally provides methods, including methods for preventing and treating HSV infection, for killing HSV-infected cells, for inhibiting viral replication, for enhancing secretion of antiviral and/or immunomodulatory lymphokines, and for enhancing production of HSV-specific antibody. For preventing and treating HSV infection, for enhancing secretion of antiviral and/or immunomodulatory lymphokines, for enhancing production of HSV-specific antibody, and generally for stimulating and/or augmenting HSV-specific immunity, the method comprises administering to a subject a polypeptide, polynucleotide, recombinant virus, APC, immune cell or composition of the invention. The methods for killing HSV-infected cells and for inhibiting viral replication comprise contacting an HSV-infected cell with an immune cell of the invention. The immune cell of the invention is one that has been stimulated by an antigen of the invention or by an APC that presents an antigen of the invention. A method for producing such immune cells is also provided by the invention. The method comprises contacting an immune cell with an APC, preferably a dendritic cell, that has been modified to present an antigen of the invention. In a preferred embodiment, the immune cell is a T cell such as a CD4+ or CD8+ T cell.
In one embodiment, the invention provides a composition comprising an HSV polypeptide. In one embodiment, the polypeptide comprises a UL49 protein or a fragment thereof. In a preferred embodiment, the fragment of a UL49 protein comprises amino acids 14-22, 21-35, 45-59, 49-57, 49-63, 105-190, 177-220 or 193-208 of UL49 or a substitutional variant thereof. In another embodiment, the polypeptide comprises an ICP0 protein or a fragment thereof. In one embodiment, the fragment of an ICP0 protein comprises amino acids 92-101, 92-105, 288-307 or 743-751 of ICP0 or a substitutional variant thereof. In another embodiment, the polypeptide comprises a UL48 protein or a fragment thereof. In one embodiment, the fragment of a UL48 protein comprises amino acids 185-197, 209-221, 288-307 or 430-449 of VP16 (UL48) or a substitutional variant thereof.
Also provided is an isolated polynucleotide that encodes a polypeptide of the invention, and a composition comprising the polynucleotide. The invention additionally provides a recombinant virus genetically modified to express a polynucleotide of the invention, and a composition comprising the recombinant virus. In preferred embodiments, the virus is a vaccinia virus, canary pox virus, HSV, lentivirus, retrovirus or adenovirus. A composition of the invention can be a pharmaceutical composition. The composition can optionally comprise a pharmaceutically acceptable carrier and/or an adjuvant.